The invention relates to a cyclone separator for a vacuum toilet system, as well as a wastewater tank and a vacuum toilet system with such a cyclone separator.
Vacuum toilet systems in aircraft utilize the pressure difference between the cabin pressure and a vacuum system—this is the outside pressure during air travel, and if the latter is not low enough, a pressure level produced by a vacuum generator—to convey the toilet contents into a wastewater tank. The low-pressure in the wastewater tank is ensured during air travel by a pipe running from the upper side of the tank toward the outer skin of the aircraft. The vacuum transport vigorously swirls the transported material. A portion of the transported material touches the pipe walls of the vacuum toilet system, to which it adheres and is conveyed relatively slowly toward the wastewater tank by the air streaming past. Another portion of the transported material is mixed in with the streaming air, and transported as an aerosol. The liquid and solid constituents of the aerosol must be separated in the wastewater tank. To ensure that the outwardly streaming air is as clean as possible, the connection between the wastewater tank and aircraft environment is currently provided with a filter of the kind shown on FIG. 2. For example, a similar filter is also disclosed in German Patent Application No. DE 102 04 248 A1 (corresponds to US Patent Application Publication No. 2003/0145372 A1).
The constant accumulation of solids may clog the filter over time. This increases the pressure loss across the filter, and impairs the transport behavior of the vacuum toilet system.